This invention relates generally to remote control fluid dispensing systems, and particularly to remote control fluid dispensing systems of the type adapted to control and display metered dispensing of fuel such as gasoline at a control station located remotely from a fuel dispensing station.
Heretofore, remote control fluid dispensing systems, such as that disclosed in U.S. Pat. No. 3,771,697, have typically employed electromechanical displays at a control station energized by electrical pulsing means mechanically coupled with the fluid dispenser at the dispensing station. The pulsing means has been powered by the AC voltage provided at the dispensing station for driving the dispenser pump. Though such systems have functioned satisfactorily for a time, they have had only marginal reliability over extended periods of time due to the presence of electromechanical type of read-outs. The fact that 60 cps voltage has driven the pulsing means has also served to limit the speed at which the dispensing of fluid may be accurately metered. As the price of fuel increases the speed at which price metering is required also increases. Recently, the prices of some fuels have risen to a point approaching the limits of 60 cps voltage counters.
Other remote control fluid dispensing systems, such as that disclosed in U.S. Pat. No. 3,523,627, have utilized DC pulse generating means at the dispensing station coupled with Nixie tube type read-outs or displays at the control station. Though the response time of such systems is greatly enhanced by the DC pulsers, it has been necessary to rewire the pumps in order to isolate the DC metering system voltages from the AC pumping system voltages. This has necessitated such reconstruction work as breaking up concrete roadways, laying separate conduit, and then resurfacing the area. This approach is obviously expensive and highly inconvenient to the conduct of business. Without circuit isolation, however, potentially dangerous AC voltage could appear at the control console within the control station in the event of a malfunction and shorting of the two electrical systems.
Accordingly, it is a general object of the present invention to provide an improved remote control fluid dispensing system.
More specifically, it is an object of the present invention to provide a remote control fluid dispensing system having an electrical metering system electrically isolated from an electrical pumping system.
Another object of the invention is to provide a system of the type described which may be incorporated into preconstructed systems using AC voltages for both metering and pumping without substantial rewiring of the circuits coupling the control station with the dispensing stations.
Yet another object of the invention is to provide a system of the type described which is highly reliable in operation over extended periods of time.